In the current Government and Binding framework, every sentence must have a subject. When the matrix subject position is non-thematic, it is filled by an expletive. Japanese, however, lacks an overt expletive. This raises the question of whether the language has an expletive which is null, or raises an embedded subject to the matrix subject position. It is argued that Japanese does indeed have a null-expletive in the course of discussing how a negative polarity item behaves in a so-called 'raising' construction. (Contains 12 references.) (Author/JL)